Compromised AWS API Key Allowed Access to Imperva Customer Data

Imperva has shared more information on how hackers managed to obtain information on Cloud Web Application Firewall (WAF) customers, and revealed that the incident involved a compromised administrative API key.

California-based Imperva revealed in late August that it had become aware of a security incident affecting customers of its Cloud WAF product, formerly known as Incapusla. An initial investigation revealed that the breach impacted customers who had accounts through September 15, 2017.

Imperva revealed last week that it learned of the compromised data on August 20 after being contacted by someone who had requested a bug bounty. The investigation launched by the company revealed — based on a detailed analysis of logs — that the data was actually exfiltrated in October 2018.

“We compared the SQL dump in the provided dataset to our snapshots and found a match. As of this post, we can say that the elements of customer data defined above were limited to Cloud WAF accounts prior and up to September 15, 2017. Databases and snapshots for our other product offerings were not exfiltrated,” explained Kunal Anand, CTO of Imperva.

Imperva says the incident is related to the process of adopting cloud technologies and migrating its user database to AWS. This process started in 2017 in response to an increasing number of customers.

At the time, Imperva developers created a customer database snapshot for testing and an internal compute instance that had been accessible from the outside. The internal compute instance contained an AWS API key, which got stolen after the instance was compromised. The attackers then used that API key to access the customer database snapshot.

The cybersecurity firm has highlighted that the data exfiltration did not involve a vulnerability in one of its products.

Imperva says 13,000 passwords have been changed, more than 13,500 SSL certificates have been rotated, and roughly 1,400 API keys were regenerated after it notified customers of the incident and advised them to take measures. The company says it has found no evidence of malicious account activity related to this incident.

“Thus far, we have not found any malicious behavior targeting our customers (logins, rule changes, etc.) and have implemented procedures to continue monitoring for such activity. We remain vigilant, however, and will continue to monitor for malicious behavior,” Anand said.

Eduard Kovacs (@EduardKovacs) is a contributing editor at SecurityWeek. He worked as a high school IT teacher for two years before starting a career in journalism as Softpedia’s security news reporter. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering.